SOMERSWORTH — A chemical combustion is believed to have caused a fire that destroyed a mobile home early Friday morning, according to Somersworth Fire Lt. Kenneth Vincent.

Fire officials are still investigating what caused the chemical reaction, which took place underneath the kitchen sink, Vincent said.

While the homeowner, Anthony Morse, and his two cats made it out of the residence safely, one firefighter was injured when he slipped at the scene. According to Vincent, the firefighter was transported by an American Medical Response ambulance o Wentworth-Douglass Hospital.

Fire Lt. Michael Spinney said Morse initially attempted to extinguish the fire by using a shovel and snow before fire crews arrived. The smoke-filled residence was evacuated before fire crews arrived.

Somersworth first responders were at the scene at 5 Short St., off Blackwater Road, until 3 a.m., while Berwick firefighters covered the Somersworth station.